postgresql/doc/src/sgml/ref/alter_view.sgml

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$PostgreSQL: pgsql/doc/src/sgml/ref/alter_view.sgml,v 1.5 2008/11/14 10:22:45 petere Exp $
PostgreSQL documentation
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<refentry id="SQL-ALTERVIEW">
<refmeta>
<refentrytitle id="SQL-ALTERVIEW-TITLE">ALTER VIEW</refentrytitle>
<manvolnum>7</manvolnum>
<refmiscinfo>SQL - Language Statements</refmiscinfo>
</refmeta>
<refnamediv>
<refname>ALTER VIEW</refname>
<refpurpose>change the definition of a view</refpurpose>
</refnamediv>
<indexterm zone="sql-alterview">
<primary>ALTER VIEW</primary>
</indexterm>
<refsynopsisdiv>
<synopsis>
ALTER VIEW <replaceable class="parameter">name</replaceable> ALTER [ COLUMN ] <replaceable class="PARAMETER">column</replaceable> SET DEFAULT <replaceable class="PARAMETER">expression</replaceable>
ALTER VIEW <replaceable class="parameter">name</replaceable> ALTER [ COLUMN ] <replaceable class="PARAMETER">column</replaceable> DROP DEFAULT
ALTER VIEW <replaceable class="parameter">name</replaceable> OWNER TO <replaceable class="PARAMETER">new_owner</replaceable>
ALTER VIEW <replaceable class="parameter">name</replaceable> RENAME TO <replaceable class="parameter">new_name</replaceable>
ALTER VIEW <replaceable class="parameter">name</replaceable> SET SCHEMA <replaceable class="parameter">new_schema</replaceable>
</synopsis>
</refsynopsisdiv>
<refsect1>
<title>Description</title>
<para>
<command>ALTER VIEW</command> changes various auxiliary properties
of a view. (If you want to modify the view's defining query,
use <command>CREATE OR REPLACE VIEW</>.)
</para>
<para>
You must own the view to use <command>ALTER VIEW</>.
To change a view's schema, you must also have <literal>CREATE</>
privilege on the new schema.
To alter the owner, you must also be a direct or indirect member of the new
owning role, and that role must have <literal>CREATE</literal> privilege on
the view's schema. (These restrictions enforce that altering the owner
doesn't do anything you couldn't do by dropping and recreating the view.
However, a superuser can alter ownership of any view anyway.)
</para>
</refsect1>
<refsect1>
<title>Parameters</title>
<variablelist>
<varlistentry>
<term><replaceable class="parameter">name</replaceable></term>
<listitem>
<para>
The name (optionally schema-qualified) of an existing view.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><literal>SET</literal>/<literal>DROP DEFAULT</literal></term>
<listitem>
<para>
These forms set or remove the default value for a column.
A default value associated with a view column is
inserted into <command>INSERT</> statements on the view before
the view's <literal>ON INSERT</literal> rule is applied, if
the <command>INSERT</> does not specify a value for the column.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><replaceable class="PARAMETER">new_owner</replaceable></term>
<listitem>
<para>
The user name of the new owner of the view.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><replaceable class="parameter">new_name</replaceable></term>
<listitem>
<para>
The new name for the view.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><replaceable class="parameter">new_schema</replaceable></term>
<listitem>
<para>
The new schema for the view.
</para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1>
<title>Notes</title>
<para>
For historical reasons, <command>ALTER TABLE</command> can be used with
views too; but the only variants of <command>ALTER TABLE</command>
that are allowed with views are equivalent to the ones shown above.
</para>
</refsect1>
<refsect1>
<title>Examples</title>
<para>
To rename the view <literal>foo</literal> to
<literal>bar</literal>:
<programlisting>
ALTER VIEW foo RENAME TO bar;
</programlisting>
</para>
</refsect1>
<refsect1>
<title>Compatibility</title>
<para>
<command>ALTER VIEW</command> is a <productname>PostgreSQL</>
extension of the SQL standard.
</para>
</refsect1>
<refsect1>
<title>See Also</title>
<simplelist type="inline">
<member><xref linkend="sql-createview" endterm="sql-createview-title"></member>
<member><xref linkend="sql-dropview" endterm="sql-dropview-title"></member>
</simplelist>
</refsect1>
</refentry>